A conventional portable electronic product with a sliding cover, such as a cellular phone with a sliding cover, comprises a body which has an input unit such as a key pad, and the sliding cover is slidably mounted to the body so as to cover the input unit of the body to prevent from unintentionally touch of the keys.
The way that the sliding cover is opened and closed can be manual, semi-auto and fully automatic, wherein the manual operation is operated by the user's hand to move the sliding cover to a desired position.
For the semi-auto operation system, U.S. Pat. Pub. No. 2005/0079902 to Chen et al., discloses a “Positioning apparatus and method for a slide cover” which comprises a first magnetic component of a first magnetic polarity configured on a first plate and a second magnetic component of the first magnetic polarity configured on the first plate, and a third magnetic component of a second magnetic polarity which attracts the first magnetic polarity and is configured on a second plate. When a relative position between the first plate and the second plate is changed to make a magnetic attraction between the first magnetic component and the third magnetic component be greater than a magnetic attraction between the second magnetic component and the third magnetic component, the second plate and the first plate moves relatively and is positioned in a first position. When the relative position between the first plate and the second plate is changed to make the magnetic attraction between the first magnetic component and the third magnetic component be less than the magnetic attraction between the second magnetic component and the third magnetic component, the second plate and the first plate moves relatively and is positioned in a second position. The sliding mechanism for the sliding cover has to be operated by the user to shift the sliding cover a distance relative to the body, the sliding cover can be moved by the user's force. The sliding cover is positioned by the attraction of the magnetic members between the body and the sliding cover.
For the fully automatic sliding cover, Jung et al. disclose “Slide type cellular phone an d sliding method thereof” in U.S. Pat. No. 7,136,688 and which discloses a first main body having a motor with a shaft and an elastic member elastically supports the motor. A switch activates the motor. A power transmitting unit is coupled to the shaft of the motor to receive a rotation power from the motor. A pinion is coupled to the power transmitting unit to be rotated by the rotation power. A second main body is slidably coupled to the first main body and has a rack coupled to the pinion and sliding with respect to the first main body according to movements of the pinion and the rack. A sliding detecting unit detects a termination of a sliding operation of the second main body to control the motor. The cover is operated by the power from the motor and the operation of the motor consumes the electric power of the battery and reduces the operation time of the cellular phone. In addition, the motor includes multiple electronic parts and mechanical parts so that impacts to the motor may damage it.